Various light-emitting devices (polymer LEDs) comprising polymers as light-emitting materials have been under review.
There is a method of forming the light-emitting layer of a polymer LED by using a solution composition containing a polymer and a solvent by an inkjet method. This method is advantageous in that large-area light-emitting devices can be fabricated at a low cost.
Known examples of such a solution composition applicable to such an inkjet method include a solution composition containing a polyfluorene derivative and a solvent (Patent Document 1); a solution composition containing a poly arylene vinylene and a solvent (Patent Document 2); and a solution composition containing an aromatic ether compound and a low boiling point solvent (Patent Document 3). In addition, there is known a device fabricated by using a mixture of 4-methyl anisole, which is an aromatic ether compound, and 1,3,5-trimethylbenzene or 1,2,3,4-tetramethylbenzene, which has three or four substituents (Patent Document 4).    Patent Document 1: WO00/59267 pamphlet    Patent Document 2: WO02/96970 pamphlet    Patent Document 3: JP-A-2004-535653    Patent Document 4: JP-A-2003-308969